Laser rangefinders are generally known in the art and may be utilized to determine the range of an object at varying distances. Laser rangefinders generally include a laser which transmits a pulse of energy toward a target. The laser energy is reflected by the target and detected by the rangefinder to calculate a distance or range to the target.
Laser rangefinders are precise instruments that require calibration and alignment to ensure an accurate detected distance. Various processes have been suggested for testing laser rangefinder systems. For example, it is known in the art to provide a range simulator or a simulated object in front of a laser rangefinder. The simulated object provides a pulse that is received by the rangefinder to simulate an object at a varying distance. A calculation of the return signal delay time may be utilized to determine the accuracy of the distance to a simulated target.
Additionally, the pulses from the target may be linked with a detector such that an operator may attempt to align or calibrate the laser rangefinder by moving the detector such that a pulse source is peaked or optimized. An operator may then attenuate the simulated transmitter source and attempt to focus to determine a best position or focusing spot associated with a photoreceiver. These varying steps may be performed over and over until an operator feels he has successfully aligned and focused a laser rangefinder.
However, the alignment and focusing is performed using an electronic signal that may be inaccurate due to various electrical connections and returns associated with the pulse signals. Additionally, such a calibration system may erroneously align various components due to the faulty signals mentioned previously. Further, such a process requires a hunt and search technique that is effort and labor intensive. The quality of an alignment and focusing utilizing such a system with large variations may result in laser rangefinder systems having varying performance characteristics.
There is therefore a need in the art for a process to optically align a photoreceiver with a laser transmitter source to provide a well aligned return on a photoreceiver as well as a focused return on the photoreceiver. There is also a need in the art for a process that reduces the labor and effort involved in alignment and focusing of a laser rangefinder that assures an accurate and repeatable alignment of multiple laser rangefinder systems.